Process of making ammonia and gas



(No Model.)

A. HENNIN. PROGESS OF MAKING AMMONIA .AND GAS.

Patented Sept. 8, 1891'.

UNITED STATES PATENT OFFICE.

ALPHONSE HENNIN, OF SPRINGFIELD, ILLINOIS, ASSIGNOR, BY DIRECT AND MESNEASSIGNMENTS, TO THE HENNIN PROCESS COMPANY, OF. ILLINOIS.

PROCESS OF MAKING AMMONIA AND GAS.

SPECIFICATION forming part of Letters Patent N 0. 459,193, datedSeptember 8, 1891.

Application filed December 24, 1889. Serial No. 334,842. (No model.)

To all whom it may concern.-

Be it known that I, ALPHONSE HENNIN, a citizen of the Republic ofFrance, and a resident of Springfield, Illinois, have invented new anduseful Improvements in Processes for the Manufacture of Ammonia and Gas,of which the following is a specification.

The object of my invention is to simultaneously and continuouslygenerate gas and ammonia from bituminous coal, shale, or other suitablefuel, and, stated broadly, I accomplish this result by introducing airand steam or oxygen and steam, the steam being preferably, though notnecessarily, superheated, into the incandescent portion of a body offuel contained in any suitable vessel or generator, regulating theamount of air or oxygen so as to maintain a zone of incandescence orbody of fire of sufficient size and temperature to decompose steam andred uee carbonous to carbonic oxide, (00 to 00,) while also maintaininga sufficient body of fuel at a lower temperature beyond such zone ofcombustion to allow of the formation of ammonia, and causing the gasesto pass off at a temperature suificiently low to prevent thedisassociation of the ammonia.

In the accompanying drawings I have shown one form of apparatus whichmay advantageously be used to carry out my process and which I myselfhave used; but I do not desire to be understood as limiting myself tothis form alone, inasmuch as any other suitable apparatus may be used,if desired, provided it is capable of carrying out the various steps ofthe process hereinafter described.

Figure 1 represents a vertical sectional view of the generator used inmy process, and Fig. 2 an enlarged view of theinjector and Washers.

A is the generator; 13, the grate; O,the ashpit; I), the feed-hopper; E,the steam-pipe coiled Within the generator-wall F F, a series ofinjecting-tuyeres with adjustable reducing-rings; G G, poker-holes; II,a pipe for the escaping gases, and I a water-main.

The generator A is made in any desired shape, preferably round, and ofsuitable refractory material. It is provided with the well-known belland hopper D, through which the fuel is fed, and holes GG, through whichthe fuel may be stirred and broken up as desired. At a point preferablya short distance above the grate B, I construct a number of radialtuyeres F, and into these tuyeres I insert steam-injectors, as shown,provided with suitable cocks or valves to control the admission of thesteam. Steam is supplied to these injectors from any boiler by means ofa pipe E, which is preferably coiled within the walls of the generator,as showu,in order to superheat 6c the steam by means of the radial heat.

A pipe H is provided to carry off the gases produced and to conduct themto a hydraulic main 1. If the air is to be used with the steam it isdrawn in through the tuyeres by means of the injectors, and the samemethod is employed with a steam and oxygen blast, the tuyeres in thiscase being connected with any suitable oxygen-supply. (Not shown.) By

placing the injecting tuyeres just above the grate I am enabled tointroduce the air or oxygen and steam to thehottest part of the fire,and to insure a more uniformdistribution and complete decomposition ofthe steam. I

also avoid the necessity of shutting off the blast when cleaning-thegrate and removing ashes, as must be done when the blast is introducedinto the ash-pit unless the ineonvenient plan of a water seal isadopted.

The water-main I is connected with any dueing-washers J J, made of anysuitable material, and shown more particularly in Fig. 2; These washersare formed with holes of different sizes, and when it is desired tocontrol the amount of air or oxygen admitted one of thewashersispushedinward, as shown at the right hand of Fig. 1, and only somuch air as can pass between the injector and the washer is admitted. Ifit be desired to lessen this amount, another washer havinga smaller holeis pushed inward, and so on. however, but one way of regulating theairsupply, and any other suitable mechanism may be used as a damper, theobject of this part of my invention being merely to control the supplyof air or oxygen admitted to the loo fuel.

The apparatus being constructed as above This is, 5

described, my process is carried out in the following manner: Bituminouscoal, shale, or other suitable fuel is introduced through the hopper andignited and allowed to burn until a bed of incandescent fuel five or sixfeet in thickness is formed. At about the same time a blast of air oroxygen and superheated steam is admitted through the tuyeres. Theproducer is then gradually filled up until the coal reaches a depth offrom ten to twelve feet, the upper portion of this charge consisting ofgreen coal drying and partially distilling. In this portion or zone,which I call the black zoue,the temperature is not allowed to rise above350 centigrade, being regulated by feeding in' fresh fuel, as required,and most of the liquid hydrocarbons of the fuel are here driven off.Immediately below this zone lies a zone of a higher temperature, inwhich the volatile matters of the coal are distilled. The temperature ofthis zone of distillation varies from 350 to 700 centigrade. Herepractically all of the volatile matters are distilled and a percentageof ammonia formed equivalent to about twenty pounds of sulphate per tonof coal consumed. Any

steam arriving at this zone of distillation is decomposed,formingcarbonic oxide (C0,) carbonous oxide (OO ,).and hydrogen (EL) andthe nascent hydrogen unites with ,the nitrogen of the coal to form anadditional amount of ammonia. The amount of carbonic oxide (00) formedin this zone is below fifty per cent. of the amount of carbonous oxide(00 since the temperature, although sufficiently high to decomposesteam, is too low to convert all of the 00 into 00, which reactioncommences at 550 centigrade, and is only completeat a temperature of1000? centigrade. Below this zone of distillation lies a still hotterzone, the temperature whereof varies from 700 to 1000 centigrade, 7

and which I call the zone of combustion. It is into this zone that thesteam and oxygen or air are introduced, as above stated. In this zone alarge amount of steam is decomposed, half of the fixed carbon of thecoal being thus oxidized, setting free an equivalent amount of hydrogen,and by then properly regulating the supply of air or oxygen theremainder of the carbon is oxidized, raising the temperature to thepoint proper for the reduction of the CO to GO. All of the nitrogen ofthe fuel is, by contact with the nascent hydrogen, set free from thefuel and converted into ammonia. The hot zone in which these reactionsoccur does not exceed, say, a few inches, and the ammonia formed thereis instantly removed by the action of the eXhauster along with any steamremaining undecomposed to a region already cooled by the reduction of 00into 00 and mostly secured in the upper zone, where decomposition ofammonia cannot occur, owing to the low temperature, and where all of thesteam remaining is decomposed.

I have by means of this process, with Very crude and imperfect means ofseparating the ammonia from the gas, obtained ammonia equivalent toabout half of the nitrogen contained in the coal, and simultaneouslytherewith obtained a fuel gas of the following composition: G0,, 6.5 percent; CO, twentynine per cent; CH 2.25 per cent; H, fortythree per cent.(Experiments at the time showed that still more ammonia was formed butescaped, owing to the imperfect condensation.) This gas is practicallyfree from undecomposed steam, and posseses the proper qualities of ahigh grade of gas for heating and metallurgical purposes, one of themain points of my process.

As far as I am awareI am the first to accomplish the conversion of fiftyper cent. or more of the nitrogen of the coal into ammonia underconditions which would allow of the reactions which take place in myprocess, especially of the conversion of the CO produced in the zone ofcombustion into 00, and thus enabling me to produce simultaneously withthe ammonia a gas very low in carbonic acid (00 and high in carbonicoxide (00.)

' The greatest care must be taken to regulate the temperature of thevarious zones. If" the temperature rises too'high, no ammonia will beformed, or, if formed, will be immediately disassociated by the heat.The ammonia and gases are allowed to pass off at a temperature lowenough to prevent the disassociation of the ammonia. They pass throughthe pipe H into the hydraulic main, from whence they are drawn into anyof the well-known apparatus for separating theammonia, removing the tarand other impurities.

I am aware'that in previous gas processes air has been heretofore usedto blow up the fire, and that after a sufiicient bed of incandescentfuel has been formed the air has been shut off and steam admitted to thefire and decomposed, and, furthermore, that air and steam have beensimultaneously admitted to the fire; but in these processes the gasesthat first pass oif from the fuel are generally burned or used to heat aseparate chamber, to which the gases created by the decomposition ofsteam, &c., are to be admitted forthe purpose of fixing or permanentlycombining them through intense heat. As this is precisely what I desireto avoid, I use no superheating or fixing chamber, nor do I consume thegases first coming off the coal, since I desire to preserve and utilizethese gases, which are among the most useful products of thedistillation. I am thus able to secure all the gases contained in thecoal for fuel purposes, and hence my process will produce more gas perton of coal than any other now known.

The object of the former process has been to obtain a fixed combined gasfor illuminatin g and other purposes, and in order to do this intenseheat has been necessary both in the generator and in the retort orfixingchamber, whereas, my object being to simultaneously produceammonia and gas, I dis? IIO would be lost in the coke of the retortgaspropense with any retort or fixing-chamber, and using merely the simplegenerator I so control the temperature at different points there of asto first decompose the steam and reduce the carbonous oxide (C0 second,to allow the ammonia to form, and, lastly, preventits disassociation.

If any ammonia has been made in the former processes for the productionof gas other than the retort or illuminating-gas process, it has been aby-product produced unintentionally and almost accidentally, and hasbeen at once destroyed by the heat that was necessarily used toaccomplish the purpose of the inventions. Its formation was a thingrather to be avoided than sought, and, it formed, it must at once bedestroyed. In the majority of prior gas processes ammonia could never beformed at all, and if formed it would last but an instantand then bedestroyed, as above stated, so that the operator would be in ignoranceof its formation and no advantage could be taken of it. In the ordinaryprocess of making illuminating-gas in closed retorts a certainpercentage of the nitrogen of the coal combines with hydrogen and formsammonia, which is collected in the scrubbers and purifiers; but thelarger portion of the nitrogen still remains in the coke and is lost. Inall previous fuel-gas processes the ammonia has been neglected, if notaltogether lost sight of. As stated before, it has either never beenformed or at once destroyed. I have, however, discovered, after carefulinvestigation and experiment, the possibility of so controlling theoperation of the generator that ammonia can not only be madesimultaneously with the fuel-gas and separated. from it withoutdetriment to the quality of the gas, but that the nascent hydrogen ofthe decomposed steam unites with most of the nitrogen, which cess. I amthus able to secure as a by-produet from three to four times as muchammonia per ton of coal consumed as is secured in the retort-gasprocess. The low temperature which I maintain in the coolest zone of thegenerator, where the gases escape, also enables me to secure, at thesame time with the ammoniacal liquors, a considerable quantity of tar ofa superior quality, thus adding still further to the value of myby-products.

The increased demand for ammonia to be used as a fertilizer and forother purposes has increased the price thereof, and consequently I amable to dispose of the ammonia I manufacture at such a price as togreatly lessen the cost of the gas produced therewith, inasmuch as itcosts little, if any more, to I produce both the ammonia and the gas bymy process than it costs to produce ammonia or gas alone.

Although I have alluded to three zones the zones of combustion, ofdistillation, and the black zonoit will be evident to any one skilled inthe art that there can be no welldefined line between them, but that onemust gradually fade into the other, and that there may be considered tobe one or more intermediate zones in which part of the reaction of eachof the principal zones may take place in a gradually-diminishing degree.

The operation, being once commenced, may be carried on as long asdesired, the gas and ammonia being simultaneously produced throughoutthe operation.

Although I have shown and described the steam and oxygen or air asentering at the same point, it will be evident that the steamblast maybe admitted at one point and the oxygen or air blast at another,provided they are simultaneously introduced. By the use of a blast ofoxygen instead of air-blast I avoid the introduction of atmosphericnitrogen, which is not only useless but positively injurious to the gas,and I am thus able to produce a hydrogenized producer gas of highcalorific value, which is practically free from nitrogen and is allcombustible, consequently m uch more economically distributed and moreefficient and valuable for fuel purposes.

I claim The process of simultaneously and continuously making gas andammonia, which consists in injecting air or oxygen and steam into a bedof incandescent fuel, controlling the temperature of the generator,first, by introducing such proportions of steam and oxygen or air as tomaintain a zone of combustion at a temperature suflicient to reduce tocarbonic oxide (00) practically all the carbonous oxide (00 formed bythe complete combustion of the fuel and to decompose practically all thesteam so introduced in the blast, and, second, by regulating the supplyof fresh fuel to maintain beyond the zone of combustion a zone ofdistillation cool enough not only to allow the formation of ammonia, butto prevent the disassociation of that already formed, leading off theammonia and gas and separatiu them by condensers, washers, or othersuitable means, substantially as described.

ALPHONSE HENNIN.

Witnesses:

WM. BARRET RIDGELY, H. H. GUsT.

